[SQL] problem with casting

[postgresql]

I have a table that has a 'date' column. In psql I tried to do a 

select proofdate::text from openjobs where jobno = '10625';

responce:   can not cast type 'date' to 'text'

Did i miss-read this section. I thought I could cast the date to text. has anyone seen 
this or am I missreading the docs?

thanks 

Ted